DENVER—A proposal to let Colorado residents carry concealed weapons without a permit failed Monday over concerns that it would make it easier for criminals and the mentally ill to have guns in public places.

A Senate committee rejected the bill on a 3-2 party-line vote, with Democrats voting against it. It’s the second year in a row the proposal has failed, but identical legislation is still running in the Republican-controlled House.

The bill would allow anyone legally able to have a gun to carry it concealed in public places, including colleges and private schools. Law enforcement officials testified against the bill, saying that removing the need for a concealed-carry permit would eliminate a safeguard authorities have to prevent some people from having weapons.

Boulder County Sheriff Joe Pelle said every year he denies conceal-carry permit requests from people who are mentally ill, are suicidal, or have substance abuse problems.

“These are people who otherwise are legally able to carry a firearm, and under this bill could carry a concealed firearm. These are people who are sometimes psychotic,” he said.

Republicans argued that they are trying to protect Second Amendment rights and that allowing law-abiding citizens to carry a concealed weapon without a permit would increase public safety because people could more easily defend themselves. Republican Sen. Tim Neville, the sponsor of the legislation, said people sometimes have to wait months before being able to get a concealed-carry permit.

“I think one of the key concerns that we have on the Second Amendment side is the actual ability of people to protect themselves. That’s what this legislation is all about,” he said.

“What they’re finding is they’re not having blood in the streets, and chaos and anarchy, and everybody going cowboy,” said Rob McNealy, speaking in support of the legislation.

Sen. Bob Bacon, a Democratic member of the committee that rejected the bill, said he worried about people being able to have firearms on college campuses, and he questioned Republicans’ argument that law-abiding citizens would be the ones taking advantage of the law.

“For me, law-abiding citizen is not a permanent condition,” he said. “All of us, on certain occasions, can snap,” he added.

As news of the deadly mass shooting at Marjory Stoneman Douglas High School in Parkland, Florida, unfolded last week, Pia Guerra, a 46-year-old Vancouver-based artist, felt helpless. She couldn’t bring herself to go to sleep, so she began to draw.

Police who find suspected drugs during a traffic stop or an arrest usually pause to perform a simple task: They place some of the material in a vial filled with liquid. If the liquid turns a certain color, it’s supposed to confirm the presence of cocaine, heroin or other narcotics.